Abstract: A magnetic switch assembly (10) is provided for detecting relative movement between first and second adjacent members (14, 18), and to defeat attempted magnetic manipulation of the assembly (10). The assembly (10) includes a pair of adjacent, superposed, upper and lower switch elements (22, 24) adapted for mounting on the first member (14), with the lower switch element (24) presenting a sloped surface (26). A shiftable, ferromagnetic ball (34) is disposed between the elements (22, 24) and movable along surface (26) between spaced upper and lower switch operating positions. A magnet (36) adapted for mounting on the second member (18) is also provided, and is oriented for normally retaining the ball (34) in the upper position thereof; however, upon movement of the member (18), the ball (34) is permitted to shift downwardly along the sloped surface (26) to the lower switch operating position thereof.

Abstract: To detect an impact due to a shock with high precision and stability, a shock sensor is employed which provides a sufficiently long closure interval of a contact of a reed switch (1) enough to carry out signal processing. A gap between an outer surface of a magnet (2) and an inner wall (8) of a housing (7) defining a passage for the magnet (2) comprises a first gap (G1) between a stationary position and an activating position and a second gap (G2) between the activating position and a stop position. The inner wall (8) is formed so that the first gap (G1) is greater than the second gap (G2). The velocity of the magnet (2) is lower when travelling in the second gap (G2) than the velocity in the first gap (G1) because air resistance is greater in the second gap (G2). Accordingly, the closure interval is increased.

Abstract: A switch assembly which is switchable between on and off positions in response to the tilting of the assembly. The switch assembly includes a magnet which is retained within a housing for gravitational movement during tilting of the assembly. The magnet is movable between a distal position, in which it is spaced apart from a magnetic switch, and a position adjacent to the switch. The proximity of the magnet to the switch causes the switch to be either electrically open or closed.

Abstract: The present invention comprises, in one embodiment, a load control apparatus comprising a control unit for controlling the supply of power to a load. The control unit has a first state and a second state. When the load control apparatus is disposed in the first state, the control unit enables power to be supplied to the load. When the load control apparatus is disposed in the second state, the control unit prevents power from being supplied to the load. The load control apparatus further comprises a switch for causing the control unit to switch from one state to another. The switch is actuatable external from the control unit.

Abstract: Assembly for unidirectional magnetic proximity detecting wherein a magnet is used in conjunction with a permeable plate for absorbing magnetic flux and a reed type switch. The switch contacts remain open due to the absorption of the magnetic flux away from the contacts and into the permeable plate. Proximation of a permeable target object near the magnet enhances the magnetic flux creating an opposite magnetic flux across the switch contacts; thus, actuating the switch closed. Proximation of the permeable target object is only effective in actuating the switch when it approaches the sensing area defined adjacent to the magnet portion opposite the permeable plate. A preferred apparatus includes an enclosure which provides a weatherproof environment for the detector assembly.

Abstract: A switch assembly has a magnet (26) mounted for in the vicinity of a reed switch (20). A weight (29) is movable in a direction generally perpendicular to the magnet (26), and is connected thereto by a mechanism (16;38,39,40;44) which translates the movement of the weight to movement of the magnet. The magnet (26) and reed switch (20) are configured so that the reed switch actuates on movement of the magnet.

Abstract: A replaceable ink reservoir for an ink printer [means comprises a means to] prevent unauthorized refilling and includes[. This means can be composed of] a magnetic contact element [(13)] arranged in the ink reservoir or [can be composed of] a clack valve arranged in the delivery region of the ink reservoir.

Abstract: A synchronizing circuit includes two switches for synchronizing the feeding of documents of a document feeder to the insert path of an insertion machine which is operative in accordance with a predetermined machine cycle to establish a given level of vacuum in a vacuum lines. The first switch closes in response to a given level of vacuum in the vacuum line and a rotary magnet driven by the insertion machine causes the second switch to close and then open at given machine cycles. The second switch and the first switch are in series with the document feeder; and, the second switch is operative to be closed and be held closed by the rotary magnet so that the document feeder is operative only upon the occurrence of both a given level of vacuum in the vacuum line and the predetermined proximity of the rotary magnet to the second switch.

Abstract: An economical and accurate tilt switch, which incorporates a reed switch, a small disc shaped magnet, and an enclosed track in which the magnet is allowed to roll just enough to affect the contacts of the reed switch. Invented to replace the well known mercury switch, but avoid the environmental hazards of mercury poisoning. The present tilt switch can be adapted into many different designs providing a wider range of switching characteristics than that of the old mercury switch.

Abstract: Four magnetically actuable reed switches are configured in a unique biasing configuration and physical arrangement for providing a defeat resistant interlock/monitoring system with minimal switching circuitry. The switches are physically arranged so that two switches, mechanically biased in a normally closed state, lie between two switches, mechanically biased closed but magnetically biased in an open state, and are mutually perpendicular. The relative positions and orientations of the biased and nonbiased switches require two separate magnetic fields to activate the system. The system is only activated by an actuator which emits the magnetic fields required to actuate only the magnetically biased switches. The actuator magnet fields are oriented in the same direction as the biasing magnet fields. Adjustability of biasing magnets and a minimal number of switches and actuation magnets increase reliability of the system despite variations in actuator position.

Abstract: A shock sensor achieving the advantages of extended minimum dwell and extended total dwell employs a reed switch in a housing mounted coaxial to the reed switch. The shock sensor employs a magnet of cylindrical shape, which is coaxial with the reed switch and slidably mounted to activate the reed switch. The shape of the activation magnet, which also serves as an acceleration detecting mass, is that of a cylindrical shell which extends along the axis of the reed switch. The shell has a ring portion extending radially inward and of short axial extent on the end of the magnet which lags in activation. A spring extends between an abutment and the magnet within the shell. When the shock sensor is subjected to an acceleration, the magnet is moved by the acceleration force from a non-activating position. Further extending the activation dwell time of the sensor and, in addition, providing an extended minimum dwell time, is the shape of the magnetic field created by the ring at the first abutting end of the magnet.

Abstract: A temperature operated switch construction, terminal block therefor and methods of making the same are provided, the switch construction comprising a housing, a movable switch arm carried in the housing, a temperature actuated unit disposed in the housing and being operatively interconnected to the switch arm to cause movement of the arm between operating positions thereof in relation to the temperature being sensed by the temperature actuated unit, the housing comprising a main part and a removable terminal block carried by the main part, the terminal block carrying a switch unit that is operatively associated with the switch arm so that the switch unit is in a first condition thereof when the switch arm is in a first operating position thereof and the switch unit is in a second condition thereof when the switch arm is in a second operating position thereof, the switch unit comprising a reed switch and the switch arm carrying a magnet for operating the reed switch to the conditions thereof as the switch arm

Abstract: A logic level interlock device for an electrical contactor having an armature carrying separable contacts is provided. The interlock includes a plunger which is movable with the armature as the armature moves between its open and closed positions. A logic level sensing means is provided adjacent the plunger. An activation means which is sensed by the logic level sensing means is carried by the plunger member. In one embodiment of the invention, the sensing means is a set of magnetic reed switches which are activated by a permanent magnet carried on the plunger. In another embodiment of the invention, the sensing means is an opto-coupler circuit. The activation means carried on the plunger is perferably an opening which allows the infrared radiation to pass through to the receiver portion of the opto-coupler. In accordance with yet a further embodiment of the invention, the sensing means are two inductive sensing elements which are activated by a permanent magnet or a ferrite bead.

Abstract: A shock sensor has a housing defining an axially extending bore, a reed switch is centered within the bore by means of its axially extending leads and a transverse section of the housing which has an axially extending hole which centers one of the leads of the reed switch with the housing. The other lead of the reed switch is centered by a first retainer, which is fixed within the bore to align the reed switch within the housing with the axis of the housing. An activation magnet, is slidably mounted within the bore of the housing, and has a central hole passing over one of the axially extending leads. The magnet is biased by a spring away from the end activation region of the reed switch, which is near an end of the glass capsule which encloses the reed switch. The spring biases the activation magnet against a second retainer so that when the housing is not undergoing acceleration the activation magnet is biased to a position where the switch is not activated.

Abstract: A switching device which uses a pivotable switching element carrying a first magnet and a movable component carrying a second magnet mounted adjacent thereto, the north and south poles of the magnets being arranged so that, when the movable component is moved to a first location, the magnets attract and the pivotable element is in a first switch position and, when the movable component is moved to a second location, the magnets repel and the pivotable element is in a second switch position.

Abstract: A fluid detection device designed to detect the presence of fluids in a flowing or non-flowing state and having the ability to energize or de-energize large current devices such as a swimming pool pump motor. It is equipped with a fluid detector tube designed to be mounted to a vertical fluid carrying conduit such as an intake to a pump. The fluid detector tube has an internal float with permanent magnet and a normally open magnetic reed switch mounted to its exterior. The float with permanent magnet at its highest vertical position closes the magnetic reed switch's contacts and activates a phase shift network. The current through the reed switch is less than fifteen millamps. The phase shift network forward biases a diac which in turn forward biases a traic. The traic completes the connection from a power source to a large current device. The de-energize state of the traic is stabilized by a snubber network. The energize state of the traic is stabilized by the phase shift network and diac.

Abstract: A temperature operated switch construction, terminal block therefor and methods of making the same are provided, the switch construction comprising a housing, a movable switch arm carried in the housing, a temperature actuated unit disposed in the housing and being operatively interconnected to the switch arm to cause movement of the arm between operating positions thereof in relation to the temperature being sensed by the temperature actuated unit, the housing comprising a main part and a removable terminal block carried by the main part, the terminal block carrying a switch unit that is operatively associated with the switch arm so that the switch unit is in a first condition thereof when the switch arm is in a first operating position thereof and the switch unit is in a second condition thereof when the switch arm is in a second operating position thereof, the switch unit comprising a reed switch and the switch arm carrying a magnet for operating the reed switch to the conditions thereof as the switch arm

Abstract: A variable differential switching apparatus comprising first structure for forming first and second magnetic fields presented sequentially along a travel path, the first field being stronger than the second field; and second structure, including a field responsive element, presented for relative travel along the path in opposite directions, the element and fields and travel path characterized in that as the element encounters the first field during relative travel in one of the directions in unlatched condition, the element is displaced by the first field into a latched condition, and as the element encounters the second field, it remains in the latched condition, and as the element continues to relatively travel in the first direction beyond the second field, it returns to unlatched condition; the element and fields further characterized in that as the element travels oppositely along the travel path, it remains in unlatched condition as the element encounters the second field, and thereafter as the element

Abstract: A plunger-operated switch assembly, useful for sensing the presence of a movable object such as a door or window, in which a magnetic reed contact is actuated by a magnet in the form of a disk-like roller plunger, or by a smaller magnet carried in the center of a roller plunger. The roller plunger is located in a cavity defined by a housing and projects through an aperture in a face plate including a flange by which the housing can be mounted recessed in a desired location. The magnetic reed contact is held alongside the cavity containing the roller plunger, so that the housing can be compact. A magnetic electrical conductor lead connected with a magnetic reed is located so as to be effectively within the magnetic field of the actuating magnet when the roller plunger is depressed a small distance so that the magnetic reed switch is actuated by a small movement of the plunger.

Abstract: A magnetically actuated float switch assembly for use with a submersible pump, comprises a float rod with two spaced stops, a movable float carried by the rod which moves between the stops in response to fluid level, the rod being mounted in a vertical oriented position for movement upwardly and downwardly in response to float movement against the two spaced stops, a magnetic body carried at the upper end of the rod for movement therewith, a generally U-shaped magnetic follower element with two spaced, magnetically responsive arms on one side of the magnetic body, or two sets of arms disposed on either side of the magnetic body to provide a dual U-shaped arrangement, the follower element being rotatably mounted with the arms thereof in a generally horizontal position, one above the other for movement of the arms thereof upwardly and downwardly in a vertical plane, the arms and magnetic body being positioned relative to each other so as to dispose the magnetic body for movement from arm to arm to thereby allow

Abstract: In a copier or printer a magnetic switch system is often used to indicate or signal the separation, mating, alignment or docking of components movable relative to one another, by the actuation or non-actuation of a magnetic switch on a first such component, such as a fixed frame member, by a magnet or a second such component, such as a manually movable tray, which magnet and magnetic switch are positioned such that as the components are moved together and docked the magnet actuates the magnetic switch.

Abstract: Apparatus for proximity magnetic switching wherein magnet assemblies are used in combination with magnetic reed switches by placement of the reed switch axis in a magnetic field null position which is shifted or unbalanced by proximation of certain magnetic materials to actuate the magnetic reed switch. In particular, such proximity magnetic switch is made weather proof and entirely sealed from its environment by molding the magnet assembly and reed switch assembly in fixed orientation within a potted compound which then exposes an actuating surface for sensing the presence of a magnetically permeable material.

Abstract: An adjustable signalling gauge may utilize a non-captivating, magnetically actuated switch element which is mounted in an influence zone of the path of a magnet carried by an indicating pointer of a gauge. The gauge may be easily adjusted by an indirect adjustment mechanism. The adjustment may be by a reducing gear. Indirect adjustment effectively allows a reduction in the torque required to change the switching threshold.

Abstract: A connector comprising a carrier body with at least two contact elements and a magnetically actuatable switching device. The switching device is arranged to electrically connect or disconnect the two contact elements when the connector mates with or disconnects from another connector. Control means activate the switching device. The control means includes a movably disposed tracer finger. In a preferred embodiment, the switching device includes a reed relay which is activated by a permanent magnet.

Abstract: An electric motor control unit for use in a vending machine includes a sealed housing containing an electric motor drivingly connected through an eccentric and a cam follower to a magnetic switch actuator operatively associated with a sealed, magnetically operated reed switch. Energization of the electric motor rotates an output shaft carrying the eccentric for one cycle of operation, whereupon the motor is deenergized to complete the cycle.

Abstract: A self-aligning oil level sensing switch is provided with an elongated float shaped to pass freely through a threaded aperture in the side of an engine crankcase as a switch housing is screwed into the aperture. The float is free to rotate about one end of a mounting rod, and is unsymmetrical about its center of mass such that it is automatically aligned by gravity into its intended operating position, regardless of the final rotative position of the switch housing. The mounting rod is pivotally and rotatably mounted on the switch housing and has an opposite end provided with a counterweight which is unsymmetrical and is free to rotate with the rod. A magnetically actuated switch mechanism includes a spring-biased magnet enclosed in a conductive sleeve which is electrically coupled to a first connector pin. The sleeve is positioned within an electrically-conductive, magnetically-transparent cover member electrically coupled to a second connector pin.

Abstract: A magnetic impact sensor for motor vehicles with a safety system such as an airbag or belt tensioner for an occupant restraint system, has a circuit breaker arranged in an electrical trigger circuit of the safety system for inflating the airbag or tightening the belt by closing the trigger circuit in response to an acceleration or deceleration effective beyond a prescribed time duration. For this purpose a magnet in combination with specially shaped pole pieces forms two magnetic circuits the magnetic conductances of which are influenced by the position of a ferromagnetic ball that moves in response to an impact relative to the pole pieces to thereby open or close the circuit breaker. Normally, in the absence of an impact the ball is in a first position that keeps the circuit breaker open. When an impact occurs the ball moves into a second position to close the circuit breaker and thus the trigger circuit.

Abstract: A splice block for use with a condition responsive security switch is provided. The splice block is generally cylindrical and mounted to the end of the switch with terminals unitarily extending therebetween. The splice block includes a base and a cover which is mountable in alternate first and second positions on the base. The first position permits wires to be inserted into the splice block. Movement of the cover into the second position terminates the wires to terminals in the splice block.

Abstract: Various embodiments of sensors are disclosed which contain an inertial mass that is magnetically biased to an initial position. In response to a certain deceleration, the mass is caused to swing about an axis and operate a switch. In some embodiments, the switch is one that is held open by the inertial mass' presence in its initial position and closes when the inertial mass swings away from its initial position, while in other embodiments it is one whose contacts are bridged by a conductive portion of the inertial mass only after the inertial mass has been displaced from its initial position, while in still other embodiments it is a reed switch that is magnetically operated. Motion of the inertial mass can be undampened or dampened. If dampening is desired, it can be accomplished either pneumatically or electromagnetically.

Abstract: A magnetic switch assembly for an electrical circuit includes a switch housing with a cavity formed therein and at least one magnetically attractable electrical contact member exposed within the cavity. One or more electrically-conductive magnetic pole members are movably disposed within the cavity, with a magnet being secured to the pole members for movement therewith. The pole member or members and the magnet are movable in the cavity between a first position in electrical contact with the contact member in order to complete electrical continuity of the electrical circuit, and a second position spaced away from the contact member in order to break electrical continuity of the electrical circuit. A movable and magnetically attractable striker member is disposed for movement toward and away from the switch housing cavity, such as on a pivotal or hinged accessory cover.

Abstract: A housing for a surface-mount magnet and magnetically sensitive switch unit pair for use in an intrusion detection device. The switch and magnet units include a generally cylindrical housing member formed with a hollow interior cavity, which contains the switch or magnet. The exterior surface of the housing member is threaded and has an end cap formed to receive a screw driver. The units are installed by screwing the housing member directly into the supporting structure. The housing member of the switch unit is further formed with a laterally projecting positioning surface for postioning the switch unit against a surface of the door or window assembly and determining the depth to which the unit is inserted.

Abstract: A reed switch holder assembly for detecting the passage of a magnet adjacent the assembly. The assembly includes a reed switch and first and second terminal elements each including a lead-receiving ferrule and a portion for mechanical and electrical connection to a conductor. The ferrule has a spring finger for holding a lead of the reed switch which finger includes a portion extending transversely from the remainder of the ferrule. The reed switch holder of the assembly includes a base of one-piece molded thermoplastic construction and a cover of one-piece molded thermoplastic construction. The base and cover include a latching mechanism for holding the base and cover assembly which, in their assembled condition, define a central cavity for holding the envelope of the reed switch and a pair of side cavities for receiving the leads of the reed switch and the ferrules of the terminal elements. One side cavity extends to a first end of the holder and the other side cavity extends to the holder second end.

Abstract: A deceleration switch comprising a support member, a permanent magnet mounted on the support member and displaceable from a first position to a second position by inertia caused by a predetermined deceleration of the support member, a spring mounted on the support member for biasing the permanent magnet toward the first position, a set of electrical contacts mounted on the support member and operable to close under the influence of the magnetic field of the permanent magnet when the permanent magnet is in the second position and an inductive device energized to produce a second magnetic field enhancing the magnetic field of the permanent magnet thus causing the contacts to remain closed for a longer period of time upon return of the permanent magnet to its first position under the biasing action of the spring.

Abstract: A signalling gauge may utilize a non-captivating, magnetically actuated switch element which is mounted in an influence zone of a path of a magnet carried by an indicating pointer of the gauge. The gauge may operate despite the presence of dust, dirt or other pollutants for an extended period of time without inducing sparks or arcing often associated with electromechanical contacts. Hall effect switch elements such as latches or digital switches may be utilized as a switch element for signalling to drive an audio or visual alarm or a digital signal.

Abstract: An acceleration and deceleration sensor includes a housing; first and second elongate cavities formed in the housing and extending parallel to one another; a reed switch disposed in the first cavity; a first elongate permanent magnet immovably secured in the second cavity; and a second elongate permanent magnet longitudinally slidably received in the second cavity and arranged end-to-end relative to the first magnet. The reed switch and the second magnet are arranged with respect to one another such that upon movement of the second magnet the magnetic field thereof actuates the reed switch. The sensor further has a lid cooperating with the first cavity and has a closed and an open position. In the closed position the lid covers the first cavity and is supported on the housing and in the open position the first cavity is exposed to environment external to the housing.

Abstract: A rotary electrical switch is provide for a portable power operated surface treating device having a fixed handle assembly, a hollow generally cylindrical roller supported for rotation on and relative to the handle assembly, and an absorbent generally cylindrical applicator sleeve coaxially supported on said roller for rotation therewith. The roller is driven by an electrical motor contained within it and powered by a rechargeable battery also supported within the roller. Operation of the motor is controlled by the rotary electrical switch which includes a pair of magnetically responsive electrical switch contacts contained within the roller and a magnetic switch actuator mounted on the handle assembly.

Abstract: Disclosed herein is a mounting structure of a reed switch in an eddy-current-type indicator which can realize to lessen an operation vibration sound of the reed switch. The mounting structure comprises a housing, a magnet rotatably provided in the housing, a pair of terminals mounted on the housing, a reed switch for detecting the number of the rotation of the magnet by generating pulse corresponding to the rotation of the magnet, the reed switch having a pair of leg portions electrically connected to the terminals, respectively, and cushion members for preventing vibration generated in the reed switch when it is operated from being transmitted to the housing and terminals. The cushion members elastically contact with the leg portions of the reed switch, so that the operation vibration is absorbed by the cushion members.

Abstract: Apparatus including a magnet (10) having at least one degree of freedom w respect to a first member, tangent to the direction of measurement and cooperating with a magnetic portion associated with a second member, and a sensor (11) for picking up the position of the magnet relative to the first member. Such apparatus is employed in steerable railway vehicles.

Abstract: An interlock switch for the service door of a computer. The switch prevents power from being automatically resupplied to the computer if the door is opened while power has been interrupted, even if the door is subsequently closed. The interlock switch includes a magnetic reed switch, an electromagnet for closing the reed switch contacts when the power-on switch of the computer is actuated, and a permanent magnet which holds the reed switch contacts closed as long as the service door has not been opened. The reed switch and electromagnet are mounted on the frame of the cabinet of the computer. The permanent magnet is mounted on the edge of the service door adjacent the reed switch. The use of the switch in a security system is also disclosed.

Abstract: A threadably installable intrusion detection unit. The unit has a generally cylindrical housing with an exterior threaded surface and an end portion formed to receive a screw driver. An operative intrusion detection element, such as a magnetic or a reed switch, is contained within the hollow interior of the housing.

Abstract: The electric and/or electrical sensor or detector device is intended to cooperate with a movable element surrounded by a shell, it comprises an annular clamping collar adapted to be clamped in position on a shell and connected to at least one connecting conductor, the collar carrying at least one mechanical and electrical removable member for connection to a removable detector element and the device is applied to a position detector to be quickly and removably secured onto a fluid cylinder body.

Abstract: The electric push-button switch comprises a housing portion and a linearly moveable push-button portion. Guide columns at the housing portion and the push-button portion attain accurate linear guiding and rotational positioning of the push-button portion. These guide columns mutually interact or interengage and are in multiple line contact with one another. This multiple line contact extends in the direction of movement of the push-button portion. The length of such line contact is variable between a rest position and an operating position of the push-button portion. This line contact is greatest when the push-button portion assumes its operating position. A contact surface of a fixed counter contact comprises a planar slide surface for resilient contact arms carried by the push-button portion. The friction arising during the forced sliding movement of the resilient contact arms over the contact surface produces self-cleaning of the contacts and damping of contact chatter movements.

Abstract: A device is presented which warns parents that their children are being abducted by sounding an alarm. The alarm is wired to a battery and a magnetic switch comprised of two magnets. When the two magnets are separated the alarm sounds. The magnets are situated in a manner in which one magnet opposes the other magnet. An attachment mechanism may be used to hold the two magnets in place. The magnets may be situated in a stuffed animal or the like. One magnet has a string attached, which is further attached to the child. When the child is separated from the stuffed animal, the magnets are separated and the alarm sounds warning parents that their child is in danger.

Abstract: An extended dwell shock sensing device (10) is constructed to operate in two stages. A carriage (34) that includes a magnet (40) is slidably mounted between a first abutment (20) and a second abutment (22). The carriage (34) also includes a cradle (52) in which a non-magnetic mass (54) is slidably mounted between a first wall (53) and a second wall (55). At a rest position, the carriage (34) is biased away from the second abutment (22) by a spring (50) and the non-magnetic mass (54) is biased away from the second wall (55) by a spring (58). A reed switch (24) is mounted to be responsive to the position of the magnet (40). Upon application of an acceleration force, the shock sensing device (10) operates in two stages. In a first stage, the carriage (34) travels to a position where it approaches the second abutment (22), and activates the reed switch (24). In a second stage, the non-magnetic mass (54) travels toward the second wall (55).

Abstract: A sensor comprising: an inertial mass movable from a first position to a second position in response to a acceleration (deceleration) signal of predetermined amplitude and duration; electrical contacts and a conductor on the inertial mass for indicating that the inertial mass has moved to the second position; an electrical conductor, reactive with other elements of the sensor for generating an electro-magnetic force tending to dampen the motion of the inertial mass; and a magnetically attractive element or magnet for biasing the inertial mass towards the first position.

Abstract: A magnetic amplifier housing uses a base, dowel and shunt to magnetizable terial to concentrate the magnetic field of a ring magnet through a Hall Effect transistor to provide an improved detector device with increased gain. The detector device causes polarity reversal when tampered with, ensures positive mechanical alignment of the transistor and mechanical components, and protection of the transistor from mechanical damage.

Abstract: The present disclosure is directed to an improved burglar alarm which is mounted on a base having a concaved space for receiving therein a ring-like magnet with an elongated resilient arm, vibratable as a result of external force, and a magnetic switch tube actuated in response to the vibrating magnet which changes either the magnet polarity or intensity of the magnetic force thereof so to produce signals to actuate a connected alarm apparatus.

Abstract: A reed switch device comprises a pair of magnets such as bar magnets or ring-shaped magnets which are arranged in inverted polar orientations such that they produce magnetic fields acting in opposite directions, and a reed switch which is movable relative to the pair of magnets such that the longitudinal axis of the reed switch is maintained substantially in parallel with the axes of magnetization of the magnets. The relative position between the reed switch and the magnets is detected through activation of the reed switch between on and off states caused in response to a change in the relative position between the pair of magnets and the reed switch.

Abstract: The improved magnetic proximity detector includes a tubular housing, a tubular magnet fixed in position within the housing, a first movable magnet within the housing at one end of the tubular magnet, a second movable magnet with the housing at the other end of the tubular magnet, an annular magnet positioned in surrounding relationship to the housing and being adjustable axially with respect to the housing, a switch having a blade, a first contact and a second contact, a connection extending between the first and second movable magnets and to the switch blade to move the switch blade responsive to movement of the magnets, the poles of the first movable magnet arranged so that the magnet is attracted to the tubular magnet, the poles of the second movable magnet arranged so that the magnet is repelled by the tubular magnet, the end of the housing containing the first movable magnet moving the two magnets responsive to ferrous metal in close spaced relationship to such end to change the position of the blade swi

Abstract: A switch for providing signals indicating the position of a rotary shaft has an enclosed switch chamber. Within the chamber is at least one magnetically actuated switch device. A switch actuating magnet is mounted in a holder exterior of the chamber and coupled to the switch through a wall of the switch housing. The holder is flexibly mounted to the housing and connected to the rotary shaft. The magnet is held in a constant rotational plane with respect to the switch.